DESIGN : DEAR PLUMBERS 39
The ‘ why ’ and the ‘ what ’ of a works information document
By
D . S ( Vollie ) Brink Pr . Eng . MSAICE , MPMISA
The history of Building Water Services , also called Wet Services , explains the ‘ why ’, and the document contents explains the ‘ what ’.
In the past the engineer or technician would mark-up the drawings indicating the services and then the draughtsman / draughtswoman would do the drawings or a ‘ tracer ’ would do the final drawings . This was before there were Technologists .
The drawings were the main element of the documentation from the design to the contractor for construction .
The only other documentation was the ‘ Bill of Quantities ’ and used by the quantity surveyor . There was also documentation to specify materials , fixtures , and equipment ; and in many cases without consulting the design engineer , however this was standard practice in those days .
The design engineer is responsible for the design and for the specifications and all the other technical construction information including the regulations and compliance , but the engineer did not exercise full control .
This led to the practice of ‘ notes ’ all over the drawings , to communicate the critical and relevant technical information for construction and installation to the contractor .
This practice of having notes all over the drawings was not very efficient and was cumbersome , and in many cases , notes were not easy to read or to follow and often an instruction was not applied .
I then started to develop a set of A4 format standard drawings to include the details of notes on the drawings , and this eventually contained all the specifications and Quality Assurance ( QA ) systems and basically all the engineering information for construction and installation .
This document eventually became our ‘ Works Information Document ’ ( WID ), which has been developed over many years since the 1970s .
The what What must be in the WID ? The WID is primarily a document with information . This information must address the design , and the construction . The design is very important because it is part of a process to explain how the system has been designed , on what standards the design was based , what the design assumptions were , was the design based on standards or was it based on first principles as a Rational design ? Was it designed on norms and standards of the owner , as some developers have their own design standards ?
The design and specifications must be clearly documented and submitted to the owner for approval , this can be a separate document which can later be incorporated in the WID .
The design assumptions are the basis of the design and must be acceptable for the owner as it will determine the ‘ degree of comfort ’ which will determine the cost of the project .
This is a process which must also be carried out in terms of the PROCSA appointment , but the result must be a final document which contains all the relevant design information and all the construction information to allow the contractor to render the best quality product in compliance with the project description and performance required and in compliance with all legal requirements and as agreed and approved / accepted by the owner or his / her representative ( s ).
The information must be in detail and to allow the contractor to know exactly what to do and how to do it .
The information must be in such detail that a bill of quantities is not even required and that the work can be done on a lump sum basis or if necessary , with a bill of quantities .
VOs can then also be addressed by means a lump sum cost per VO as the work progress . The advantage is that when the project is complete , the final cost is also final .
If this ‘ lump sum ’ type of contract is preferred , then it could be an NEC contract .
The Building Water Services Department ( Wet Services ) have an excellent example of a WID which can be used as a basis for the other services such as Electrical , Mechanical , Structural , and Civil . PA
Kind regards ,
Vollie
Vollie Brink is one of the industry ’ s longestserving wet services engineers . He continues to serve on SABS committees and has been involved in the Green Building Council ’ s Green Star rating system . Brink continues to consult for various organisations while enjoying a wellearned retirement .
“ If this ‘ lump sum ’ type of contract is preferred , then it could be an NEC contract .”
September 2021 Volume 27 I Number 7 www . plumbingafrica . co . za